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-rw-r--r--toolkit/crashreporter/google-breakpad/src/common/linux/elfutils.cc194
1 files changed, 194 insertions, 0 deletions
diff --git a/toolkit/crashreporter/google-breakpad/src/common/linux/elfutils.cc b/toolkit/crashreporter/google-breakpad/src/common/linux/elfutils.cc
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+++ b/toolkit/crashreporter/google-breakpad/src/common/linux/elfutils.cc
@@ -0,0 +1,194 @@
+// Copyright (c) 2012, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "common/linux/elfutils.h"
+
+#include <assert.h>
+#include <string.h>
+
+#include "common/linux/linux_libc_support.h"
+#include "common/linux/elfutils-inl.h"
+
+namespace google_breakpad {
+
+namespace {
+
+template<typename ElfClass>
+void FindElfClassSection(const char *elf_base,
+ const char *section_name,
+ typename ElfClass::Word section_type,
+ const void **section_start,
+ size_t *section_size) {
+ typedef typename ElfClass::Ehdr Ehdr;
+ typedef typename ElfClass::Shdr Shdr;
+
+ assert(elf_base);
+ assert(section_start);
+ assert(section_size);
+
+ assert(my_strncmp(elf_base, ELFMAG, SELFMAG) == 0);
+
+ const Ehdr* elf_header = reinterpret_cast<const Ehdr*>(elf_base);
+ assert(elf_header->e_ident[EI_CLASS] == ElfClass::kClass);
+
+ const Shdr* sections =
+ GetOffset<ElfClass, Shdr>(elf_header, elf_header->e_shoff);
+ const Shdr* section_names = sections + elf_header->e_shstrndx;
+ const char* names =
+ GetOffset<ElfClass, char>(elf_header, section_names->sh_offset);
+ const char *names_end = names + section_names->sh_size;
+
+ const Shdr* section =
+ FindElfSectionByName<ElfClass>(section_name, section_type,
+ sections, names, names_end,
+ elf_header->e_shnum);
+
+ if (section != NULL && section->sh_size > 0) {
+ *section_start = elf_base + section->sh_offset;
+ *section_size = section->sh_size;
+ }
+}
+
+template<typename ElfClass>
+void FindElfClassSegment(const char *elf_base,
+ typename ElfClass::Word segment_type,
+ const void **segment_start,
+ size_t *segment_size) {
+ typedef typename ElfClass::Ehdr Ehdr;
+ typedef typename ElfClass::Phdr Phdr;
+
+ assert(elf_base);
+ assert(segment_start);
+ assert(segment_size);
+
+ assert(my_strncmp(elf_base, ELFMAG, SELFMAG) == 0);
+
+ const Ehdr* elf_header = reinterpret_cast<const Ehdr*>(elf_base);
+ assert(elf_header->e_ident[EI_CLASS] == ElfClass::kClass);
+
+ const Phdr* phdrs =
+ GetOffset<ElfClass, Phdr>(elf_header, elf_header->e_phoff);
+
+ for (int i = 0; i < elf_header->e_phnum; ++i) {
+ if (phdrs[i].p_type == segment_type) {
+ *segment_start = elf_base + phdrs[i].p_offset;
+ *segment_size = phdrs[i].p_filesz;
+ return;
+ }
+ }
+}
+
+} // namespace
+
+bool IsValidElf(const void* elf_base) {
+ return my_strncmp(reinterpret_cast<const char*>(elf_base),
+ ELFMAG, SELFMAG) == 0;
+}
+
+int ElfClass(const void* elf_base) {
+ const ElfW(Ehdr)* elf_header =
+ reinterpret_cast<const ElfW(Ehdr)*>(elf_base);
+
+ return elf_header->e_ident[EI_CLASS];
+}
+
+bool FindElfSection(const void *elf_mapped_base,
+ const char *section_name,
+ uint32_t section_type,
+ const void **section_start,
+ size_t *section_size,
+ int *elfclass) {
+ assert(elf_mapped_base);
+ assert(section_start);
+ assert(section_size);
+
+ *section_start = NULL;
+ *section_size = 0;
+
+ if (!IsValidElf(elf_mapped_base))
+ return false;
+
+ int cls = ElfClass(elf_mapped_base);
+ if (elfclass) {
+ *elfclass = cls;
+ }
+
+ const char* elf_base =
+ static_cast<const char*>(elf_mapped_base);
+
+ if (cls == ELFCLASS32) {
+ FindElfClassSection<ElfClass32>(elf_base, section_name, section_type,
+ section_start, section_size);
+ return *section_start != NULL;
+ } else if (cls == ELFCLASS64) {
+ FindElfClassSection<ElfClass64>(elf_base, section_name, section_type,
+ section_start, section_size);
+ return *section_start != NULL;
+ }
+
+ return false;
+}
+
+bool FindElfSegment(const void *elf_mapped_base,
+ uint32_t segment_type,
+ const void **segment_start,
+ size_t *segment_size,
+ int *elfclass) {
+ assert(elf_mapped_base);
+ assert(segment_start);
+ assert(segment_size);
+
+ *segment_start = NULL;
+ *segment_size = 0;
+
+ if (!IsValidElf(elf_mapped_base))
+ return false;
+
+ int cls = ElfClass(elf_mapped_base);
+ if (elfclass) {
+ *elfclass = cls;
+ }
+
+ const char* elf_base =
+ static_cast<const char*>(elf_mapped_base);
+
+ if (cls == ELFCLASS32) {
+ FindElfClassSegment<ElfClass32>(elf_base, segment_type,
+ segment_start, segment_size);
+ return *segment_start != NULL;
+ } else if (cls == ELFCLASS64) {
+ FindElfClassSegment<ElfClass64>(elf_base, segment_type,
+ segment_start, segment_size);
+ return *segment_start != NULL;
+ }
+
+ return false;
+}
+
+} // namespace google_breakpad